Build Your Own Magneto Charger

Learn more about how to build your own Magneto charger and the benefits of what a magneto charge will do for you

| April/May 2020

Photo by Peter Rooke: Recharging a Webster magneto on the homemade magnet charger. The blocks ensure a good connection with the magnets.



While a friend of mine had a magnet charger, I always felt a little uneasy about putting him to the trouble of ensuring that the battery that powered it was fully charged, and the fact he had to clear his work bench to make room to use it. Part of the satisfaction I gain from restoring engines arises from the turning of various bits of metal into a working piece of machinery, so I felt that to make a charger would be a new challenge, and that I would also learn something in the process. I knew little about electricity, apart from being able to change a plug, and knew even less about magnetism. Fortunately, I still met my old school physics teacher for a glass of beer most weeks, as we were both members of a local rifle club, more social members now with failing eyesight!

However, my hopes of an immediate flow of information just elicited the initial comment “yes, magnetism – a tricky subject,” and he started to talk about something else!

Next, I searched SmokStak and a few hours were well spent gathering numerous comments as well as printouts of articles detailing plans to build magnetizers, including a comprehensive one by John Rex printed in GEM in 1989, and a copy of an article in Dyke’s Automobile and Gasoline Engine Encyclopedia in 1918. There was also reference to a Dave Gingery design.

This was fine, but I was no further along as I now had three schemes, each one using different size cores, all of which were, according to numerous people, successful. The only common point that I was able to identify was that 20,000 ampere-turns of copper wire appeared to be the magic number to achieve the full charging of a magneto. Ampere-turns refer to the number of turns of wire around the core multiplied by the amperes that the length of wire draws.

4/28/2020 10:58:19 PM

In power source you mention connecting two 12 volt batteries in parallel to get 24 volts. You need to connect them in series if you want the voltages to add. By connecting them in parallel the current available would increase but the voltage would remain 12 volts.


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